1. Field of the Invention
This invention relates to radiotelephones and more particularly to a radiotelephone for motor vehicles using the techniques of speech recognition and synthesis.
2. Discussion of Background
So far, a radiotelephone installed in a motor vehicle is generally designed as a simple means of oral communication that resorts, for its use, to handling of a set provided with sending and receiving acoustic cells and a keyboard for dialing the numbers. Performance of these operations in motor vehicles causes difficulties for driving, both in regard to safety and comfort. For this reason, these operations are generally performed at low speed of the vehicle, even when it is stopped. Because of this, the difficulties encountered have resulted in a considerable limitation of the possibilities that could be offered by a radiotelephone in a motor vehicle.
Moreover, "hands-free" telephone installations are known. Generally a standard telephone set making it possible to converse over a certain distance is involved. Recently, some installations of this type have been equipped with a speech recognition and synthesis system to perform the operations of dialing a number or searching for previously stored numbers.
However, these "hands-free" telephone installations do not make it possible to solve all the problems raised, for reasons of safety and ergonomics particularly, by use of a radiotelephone in a motor vehicle. Further, these "hands-free" telephones make only slight use of the possibilities offered by speech recognition and synthesis techniques whose application to motor vehicles is described, for example, in the patent applications FR-A-82 16 066 and FR-A-84 01 749.